Chuck



March l5, 1932. R. M. lppARD 1,849,546

CHUCK Filed Jupe 18, 1930 Ellyn? a@ Patented Mar. 15, 1932 UNITE stares PATENT oFFl-CE.

ROBERT M. LIPPARD, OF DETROIT, MICHIGAN, ASSIGNOR TO THE HEALD MACHNE COMPANY, OF WORCESTER, MASSACHUSETTS; A CORPORATION OF MASSACHUSETTS CHUCK Application filed June U18,

` dially to engagel and disengage the work.

Vith such a chuck, usually providing three radial jaws having lwork-engaging projections 1200 apart, a difhculty is encountered in the retention of workpieces that present noncontinuous surfaces for engagement by said jaw p1ojections,-for example, workpieces such as gears, sprocket wheels and the like. With an object of this character, unless the numberof spaces between its surface projections or teeth is exactly divisible byV three (or whatever number of equally-spaced jaws the chuck may have) ,the holding points will not be equidi'stant from the center, and the object therefore will not be properlycen- ,1 tere'd in the chuck.- fleretofore, to remedy v'20 this difficulty, it has been necessary to forego the employment of the usual chuckj awgs, and to replace the same with special j awsadapted to give a more extended surface contact with the object, thereby to straddle one or morev of its projections or teeth.

According to the present invention, this dilliculty is overcome by arranging certain of the chuck jaws for limited angular ad.-

i justment, thereby to adapt them readily to the irregularities of surface of the work to be held in the chuck. @ther and further ob-v jects and advantages of the invention will be apparent from the following detailed description thereof, taken in connection with the accompanying drawings, in which- Fig. 1 is a front view of a chuck embodying my invention.

Fig. 2 is a section on the line 2 2 of Fig. l.

Fig. 3 is a top plan view of one of the jaw assemblies.

Fig. 4 is a diagrammatic view illustrating the operation of the invention.

Like reference characters refer to like parts in the different figures.

The chuck shown in Figs. 1 and 2 has a body portion constituted by an annular member 1, the latter being` adapted for attachment, as by bolts 2, 2, to a face plate 3 on the end of a grinding or other machine spindle, not shown. On the front face of annular 1930. Serial No. 462,197.

memberl are mounted, in a manner hereinafter'tob-e described, the slides 4, 4 `(here shown as 'three in number) which carry the radially movable jaws of the chuck. The several slide and jaw assemblies are all of the same construction, so that a description of one will suffice for all.

Y Each slide 4, by means of gibs 5, 5 attached thereto, provides an undercut guideway for the movement of a jaw carrier 6, the latter serving as a supportin which the Vassociated chuck jaw 7 is capable of adjustment, in and out, as desired. vTo this end, the carrier 6, as shown in Fig. 3, provides `an internal re'- cess 8 for the reception ofla--clamping block 9, the latter receiving screws 10, 10 projecting rearwardly from the jaw 7 By tightening the screws 10, 10, the clamping block 9 and jawV 7 are drawn toward each other and into engagement against opposite sides of the shoulders 11,v 11 of carrier 6, thereby to liX the position of the jaw 7 in said carrier. When the screwslO, 10 are'loosened, the jaw 7 and block 9 are free to be moved inwardly or outwardly as desired, and such movement can be effected by an adjusting screw 12,` threaded into the jaw, and mounted to turn freely, without longitudinal movement, in an overhanging bracket 13 secured In each ofthe slides 4 is a bell crank lever 14, pivoted on a transverse pin 15. One arm ofV saidlevcr is received in a suitable slot 16 formed in the rear face of the associated jaw carrier 6, so that rocking of said lever will e'ect inward or outward movement of the associated j aw, to engage it with or disengage it from the workpiece. The other inwardly extending arms of all the levers 14 are received in a peripheral groove 17 Of a centrally-located chuck-operating member 18, the latter being slidably mounted ina concentric sleeve 19 carried by the chuck body 1, which sleeve is slotted, as shown at 20, for the passage of the inwardlyeXtending-arms of the several levers 14, 14. The member 18 is i DI extending draw rod 21; when the latter' is shifted to the right, Fig. 2, the several arms 14, 14 are rocked in unison to impart outward radial movements to the chuck jaws 7, 7, thereby releasing the work; the opposite movement of said draw rod rocks the levers 14, 14 in unison to move the chuck jaws 7, 7 inwardly, for gripping the work.

In the use of a chuck of this character for the retension and centering of a gear wheel or the-like, it is the general practice to equip each awwith a projecting pin 22,-the work under these conditions being tirmly held by the reception of said pins in the spaces between its projections or teeth, as indicated in Fig. 4. However, an obstacle to this advantageous chucking method is encountered when the spacing between the teeth or proj ections of the object to be held is such as not to line up with all the pins 22, 22; in other words, it frequently happens, as shown in Fig. 4, that the spaces of the object will be ofi'set 'from one or more of the pins 22, when the later, as is the usual case with a three jaw chuck, are in equidistant relation, 120o apart. According to the present invention, this difiiculty is overcome by the provision or" angular adjust-ment igor one or more of the slides 4, 4 on the face of the chuck body 1. To that end, the front face of body 1 provides an annular recess 23 in which lits an arcuate projection 24 of each oi' the several slides 4, The rear face of body 1 is similarly recessed, as shown at 25, and in the zones of attachlnent to said body of one or more of sait slides, the recesses 23 anc 25 are connected by elongated arcuate slots 26, 26 adapted for the passage therethrough of screws 27, 27. Said screws have threaded engagement with suitable arcuate keys 28, 28, located in the recess 25; thus each slide is held in position by the clamping action produced by tightening of its screws 27, 27, serving to draw the slide and the associated key 28 toward each other, into hrm engagement with the body 1. It the spaces between the projections or the work, as shown in Fig. 4, do not permit of registry with all of the pins 22,an angular adjustment ot one or more of the slides 4 can be made, to secure such registration,-this angular adj ustment being made possible by the elongated slots 26, 26 provided for the passage oi the clamping screws 27, 27. By this adjustment, the pins 22, shown in full lines in nonregistering position, can be shifted to the registering positions shown by broken lines in Fig. 4.

It is further to be noted that, notwithstanding angular adjustments of the slides 4, 4 as above described, the radial disposition of each of said slides is invariably maintained; this is due to the reception of the arcuate projection 24 of each slide in the annular recess 23 of body 1, which prevents said slide from assuming a non-radial position on said body.

I claim,

1. In a chuck of the class described, a plurality of slidable jaws, a mounting tor each jaw in which the latter is slidable radially, and means for adjusting the mountings of said jaws, to vary the angular distance bctween said jaws, without disturbing their radial relation.

2. ln a chuck of the class described, a body portion providing slideways for a plurality of radially movable jaws, means for adjusting said slideways on said body portion to vary the angular distance between said jaws, and means for maintaining, in different positions of adjustment of said slideways, the radial relation of said jaws.

3. In a chuck of the class described, a body portion, a plurality of radially movable jaws, slideways provided by said body portion for the movement of said jaws, and means for angularly adjusting certain of said slideways without disturbing the radial relation of said jaws.

4. In a chuck of the class described, a body portion, a plurality of radially movable jaws, slideways provided by said body portion for the radial movement of said jaws, means for angularly adjusting certain of said slideways to vary the relative angular positions of said jaws, and means for maintaining the radial disposition of said jaws in dill'erent positions of adjustment of said slideways.

5. ln a chuck of the class described, a body portion having an annular recess, slideways for a plurality of radially movable aws carried by said body portion, means for angularly adjusting certain of said slideways, and an arcuate projection on each of the later litting the recess of said body portion, whereby to maintain the radial relation or" the jaws in dii'erent positions of adjustment of said slideways.

G. In a chuck of the class described, a plurality of aws mounted for sliding movement radially, means for angularly adjusting the mountings ot said jaws, to vary the angular distance between them, a lever carried by each jaw mounting, for imparting radial movement to the jaw thereof, and a centrally disposed actuator common to all of said levers, said actuator having a peripheral groove to receive the ends of said levers, whereby to maintain its operative connection therewith in all positions of angular adjustment of said mountings.

' ROBERT M. LIPPARD. 

